The Making Of A Car Bomb And Other Explosives

KNOW YOUR BOMBS

With the recent car bomb scare in New York City, several questions quickly come to the surface. For example: How does a car or truck bomb work? And how hard are they to make?

To build a car or truck bomb that works, you need a vehicle, an explosive agent, a detonator to set off the explosion and access to a sensitive area.

The car bomb found in New York had all of these elements, but apparently the detonator failed. The vehicle was a Nissan Pathfinder. The explosive agents consisted of 10 gallons of gasoline (plus any gasoline in the tank), 60 pounds of propane and some firecrackers. There was also more than 100 pounds of fertilizer in the car, although it would not have detonated because it was not bomb grade.

The detonator was an alarm clock that was rigged to ignite the firecrackers, which presumably would have lit the gasoline. The heat from the burning gas would cause the propane tanks to burst, and the propane would have created a significant fireball.

Apparently the alarm clock did not light the firecrackers, or the firecrackers did not have the desired effect, so the bomb fizzled.

The access in this case was provided by the lack of hard security in Times Square. There really isn't anything to prevent someone from driving a car into Times Square and parking it. Access to many parts of Washington, though, is tightly controlled with barriers and armed guards. It would not be possible to undertake a car bomb attack on the White House, for example, .

Even an amateur car bomb, like the one in New York, could cause significant damage if designed correctly. For example, a Nissan Pathfinder could easily hold 100 gallons or more of gasoline.

If properly detonated, this gasoline would create an impressive fireball that would kill or injure anyone standing nearby and probably damage a few buildings.

A step up from this would be ammonium nitrate fertilizer, which is a powerful explosive and relatively easy to obtain in some states. Timothy McVeigh's truck bomb in Oklahoma City, for example, used more than 5,000 pounds of ammonium nitrate, along with nitromethane racing fuel, ANFO (a mixture of ammonium nitrate and diesel fuel) and a commercial explosive called Tovex that is the modern equivalent of dynamite.

In this case, a lit fuse started a chain reaction that acted as the detonator. This was an incredibly powerful bomb that destroyed or damaged not only the intended building but several others as well.

A step up from something like an ammonium nitrate bomb would be a dirty bomb. A dirty bomb is a device designed to spread nuclear terror.

At the theoretical level, a dirty bomb might start as an ammonium nitrate car bomb. Nuclear material is then added to the vehicle so that it is spread by the explosion. At a large scale, the idea has never actually been used successfully.

Because it is still relatively difficult to obtain nuclear materials, and because the materials pose the risk of radiation poisoning to anyone handling or transporting them before the bomb explodes, the likelihood of a large dirty bomb ever being detonated is considered low. Also, it would be possible to decontaminate the affected area.

The worst-case scenario would be an actual nuclear weapon stored in a car or truck and driven into the center of a large city. The possibility of a rogue nuclear weapon being used in this way by terrorists is frightening enough that world leaders met to discuss the threat in April.

There are two possibilities here: 1, that terrorists get hold of an actual nuclear bomb, or 2, that terrorists obtain bomb-grade nuclear materials and assemble a device. In either case, the result would obviously be catastrophic. Even a small nuclear bomb could destroy much of a major city.

It would be nearly impossible to stop the creation of a gasoline-type car bomb.

But other varieties of car bombs could be prevented to some degree with better control of the ingredients. At the nuclear level, at least, the world is already taking steps in that direction.